Automobile chemical-engine.



J. A. THOMAS.

AUTOMOBILE CHEMICAL ENGINE.

APPLICATION FILED JUNE 17. 1912.

Patented May 4, 1915.

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l ismwa J. A. THOMAS.

AUTbMOBILE CHEMICAL ENGINE. APPLICATION FILED !u'NE17.'1912.

1,137,9Q'? Patented May 4, 1915.

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JOHN A. THOMAS, 015 ZANESVILTIE, OHIO.

AUTOMOBILE C HEMICAL-ENGINE.v 7

Specification of Letters Patent. PatentedMay 4, 1915,,

Application filed June 17, 1912. Serial No. 704,057.

. .particularly in my applications, Ser. -No. 657,081 and Ser. 668,824, and in one of which I show the chemical solution forced into the water on the delivery side of the engine pump, and the other and latter case the chemical is supplied or obtained by sucand associated parts.

tion on the intake side of the pump. In the present case the solution is delivered to the engine pump by a force feed or supply, as will presently be seen.

In the accompanying drawings, Figure 1 is a sectional elevation of an engine or power and the chemical supply pump and chamber Fig. 2 is a plan view of the partsshown in Fig. 1.

The engine as thus shown represents the working parts of an automobile fire engine with chemical apparatus as an adjunct to the engine pump and Water supplyv and is planned to deliver the chemical in solution and under pressure of its own to the intake side ofthe pump. This is in contradistinction to the means shown in my above mentioned application, Ser. No. 657,031, in

which the chemical pump delivers the chemical to the outgoing water from the main pump. In doing this I naturally encountered a very great back pressure which had to be overcome by the chemical pump in order to get the chemical into the stream, and this back pressure, along with the power required to operate the chemical pumpto over come the same, was liable to make such a drain upon the power of the engine that it might materially affect the output, especially under strained conditions. I therefore conceived the idea of placing the chemical supply mechanism in relations with the intake where no such back pressure is encountered and where I get the added advantage of using the main pump as an additional chemical mixing and incorporating medium. Now, having this difference in mind, I employ a double rotary pump or one which has two rotors a with intermeshing wings and mounted on parallel shafts 2 and 3 of which one, the shaft 2, is driven from power shaft 4: through pinion 5 thereon meshing with gear 6 on shaft 2. The said rotors revolve outwardly at the intake and thus pocket the water as against the wall of easing c, a construction and arrangement of parts substantially like that shown in the two preceding cases.

The chemical pump is similar in construction to the power or engine pump but smaller in size and provided with two rotors 8 in a casing d and having its intake on top and its discharge at the bottom whence the chemical is delivered by passage 10 into the water passage 12 beneath. A check valve 13 in passage 10 serves to prevent possible floodingof the chemical pump from the main passage 12 and confines said pump within its own 7 working conditions. Power for driving the-chemical pump proceeds from the pump shaft 2 by sprocket 14 to the chemical pump shaft 15 and gears 16 and-17 mesh to drive the otherwise idle rotor 8.

The chemical is supplied to the said pump by a suitable conveyer or worm 20 mounted in a cylindrical casing 21 and supplied with the dry chemical from a hopper 22. From the conveyer the dry chemical is delivered into a mixing or solution receptacle or chamber 24, which has a reduced outlet at its bottom open to the top of the chemicalpump.

A sufficient supply of water for the chemical solution is obtained by pipe connection 25' from the discharge side of the main pump, and a suitable hand controlled valve 26 in pipe 25 serves to fix the flow of water to said solution chamber, while an overflow or safety outlet is provided at 27 for said chamber. By preference at this time I use the common bicarbonate of soda as the chemical constituent, which, when incorporated with the water under conditions that necessarily obtain in this engine and projected upon a fire, will develop a volume of carbonic acid gas which is well known to be much more deadly to fire than plain water, and therefore, extinguish a fire with much less water than would be possible without it, as is now well known.

By the foregoing construction of the chemical pump a fixed amount of the solution is fed tothe engine according to the speed of rotation, and presumably, the several parts are arranged and connected up to supply just the volume of chemical to the water at all times to get the best possible results at the delivery upon the fire.

A hand lever It serves to throw the chemical pump into or out of operation through clutch n' as may be required, it belng under:

' stood that the engine can be used with or without the chemical.

A chemical fire extinguishing engine provided with a rotatable main pump consisting of two rotors having intermeshing wings anda rotary'chemical supply pump of like construction and smaller size operatively connected therewith and constructed to measme the chemical and deliver the same to the intake side of the main pump in predetermined proportions through a valved channel, in combination with a chemical receiving chamber discharging into said chemical supply pump and a fluid passage from the discharge side of said main pump to the said chamber provided with .means to contract the volume of fluid to said chamber.

In. testimony whereof I aflix my signature in presence of two witnesses.

JOHN A. THOMAS.

Witnesses:

E. M. FISHER, R. B. MOSEIL 

